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Open toolSubtitle sync tool
Subtitle Time Shifter
Fix SRT or VTT subtitles that appear consistently too early or too late. Shift every timestamp by the same number of seconds, preview the change, and download the synced file.
SRT and VTT supportMillisecond precisionRuns locally in your browser
Positive values delay subtitles. Negative values make them appear earlier.
Timing preview
The first cue will show its timing before and after the shift.
Fix a constant subtitle delay
Use a subtitle time shift when every caption is early or late by roughly the same amount. A single positive or negative offset updates the start and end time of every cue.
Positive and negative shifts
A positive value delays subtitles so they appear later. A negative value advances subtitles so they appear earlier. Decimal values such as 0.5 provide millisecond-level control.
When a time shift is not enough
If the subtitles begin in sync and become increasingly inaccurate, the problem is progressive drift. That requires timeline scaling or frame-rate correction rather than one fixed offset.
SRT and WebVTT stay in format
SRT output keeps comma-based milliseconds, while VTT output keeps dot-based milliseconds and existing cue settings. Only timing lines are adjusted; subtitle text is preserved.
How to shift subtitle timing
- Upload an SRT or VTT file, or paste the subtitle text.
- Enter a positive value to delay captions or a negative value to advance them.
- Shift the timestamps and compare the first cue before and after.
- Download the synced subtitle file and check it with the video.
Need WebVTT output?
Convert an SRT subtitle file to WebVTT after its timing is correct.
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Open stepFAQ
How do I fix subtitles that appear too early?
Use a positive time shift to delay every subtitle cue. For example, enter 1.5 seconds when the captions consistently appear 1.5 seconds before the matching audio.
How do I fix subtitles that appear too late?
Use a negative time shift to make every cue appear earlier. Enter -2 when the captions consistently appear two seconds after the matching audio.
Does this subtitle time shifter support SRT and VTT?
Yes. The tool detects standard SRT and WebVTT timing and downloads the shifted subtitles in the same format as the input.
Does this upload my subtitle file?
No. The subtitle text and timestamp adjustment stay in the current browser tab and are not sent to UseQuickKit.
Can this fix subtitles that gradually drift out of sync?
No. A fixed time shift corrects a constant delay. Progressive drift usually requires retiming against two reference points or correcting a frame-rate mismatch.
What happens when a negative shift moves a cue before zero?
A cue that partly crosses zero is clamped to 00:00:00 and reported. If the entire cue would move before zero, the tool stops and asks for a smaller shift so subtitle text is not silently removed.